Free software stalwart Richard Stallman has taken a cool view of the news that hugely-popular games developer Valve plans to make its non-free Steam platform available for Linux.

On the face of it, that a major games developer wants to hedge its bets in the Windows 8 age by porting an important platform to Linux is good news; Linux has always suffered lacked native games, now seen as a drawback to mainstream acceptance. Linux needs games.

According to Stallman, however, this is a double-edged sword that offers some benefits but also a downside that compromises the integrity of the free software philosophy.

“Nonfree game programs (like other nonfree programs) are unethical because they deny freedom to their users. (Game art is a different issue, because it isn't software.) If you want freedom, one requisite for it is not having nonfree programs on your computer. That much is clear,” said Stallman in a blog.

Many reports have focussed on Stallman’s criticism of Valve’s plans to ‘adopt’ Linux but his argument is not entirely negative. The ability to run major games on Linux might also draw more people away from their reliance on Windows, he admitted, describing the net direct effects as resulting in more good than harm.

“But there is also an indirect effect: what does the use of these games teach people in our community?,” added Stallman.

“Any GNU/Linux distro that comes with software to offer these games will teach users that the point is not freedom. Nonfree software in GNU/Linux distros already works against the goal of freedom. Adding these games to a distro would augment that effect.”

“If you want to promote freedom, please take care not to talk about the availability of these games on GNU/Linux as support for our cause.”

Another way of looking at the issue would be to argue that as Linux becomes more popular, it inevitably acquires commercial baggage looking to profit from this. Currently, the only way to run Windows software including games is to use emulators such as Wine but these come with niggles such as compatibility, security and (in some cases) lower performance.

According to Valve head and former Microsoft employee Gabe Newell, Valve was investing in a Linux port after describing Windows 8 as "a catastrophe for everyone in the PC space."

The new OS included a Microsoft’s own Windows Store, which could make it harder for third-parties to flourish thanks to the 30 percent cut taken from every sale.

"There's a strong temptation to close the platform because they look at what they can accomplish when they limit the competitors' access to the platform, and they say, 'That's really exciting,'" said Newell.